Damping device and method for motor-driven power steering
By estimating and compensating for interference signals in the MDPS system through adaptive control and filtering modules, the problem of vehicle vibration transmission to the driver is solved, resulting in significant vibration reduction and improved driving comfort.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HYUNDAI MOBIS CO LTD
- Filing Date
- 2022-02-28
- Publication Date
- 2026-06-19
AI Technical Summary
In existing technologies, MDPS systems are subject to interference from factors such as vehicle body structure imbalance and road conditions during vehicle operation, causing vibrations to be transmitted to the driver, affecting the driving experience. Furthermore, the frequency changes with vehicle speed, making it difficult to effectively reduce vibrations.
The adaptive control module and the adaptive filtering module estimate and inversely compensate for the interference signal of the MDPS system, generate compensation signal and filter signal, reduce the interference component in the current command, and control the motor to reduce vibration.
It effectively reduces the vibration of the MDPS system, improves the driver's driving experience, and achieves a vibration reduction of more than 60% without the need for complex dynamic modeling, simply through numerical calculation.
Smart Images
Figure CN115593499B_ABST
Abstract
Description
Technical Field
[0001] Exemplary embodiments of this disclosure relate to a vibration damping device and method for an MDPS (motor-driven power steering), and more specifically, to a vibration damping device and method for an MDPS that can estimate disturbances applied to the MDPS and compensate for the disturbances in reverse, thereby reducing vibrations. Background Technology
[0002] MDPS determines the vehicle's driving status using a torque sensor to measure the steering torque input to the steering wheel by the driver, a steering angle sensor to measure the steering angle or steering angular velocity of the steering wheel, and a vehicle speed sensor to measure the vehicle speed. When the driver operates the steering wheel, MDPS provides auxiliary torque via a motor based on the steering torque applied to the steering shaft.
[0003] Various types of vibrations can be generated in the steering system of a vehicle in which such an MDPS is installed. The vibrations generated in the MDPS can include various vibrations generated in the rotational and radial directions of the wheels due to structural imbalances in the vehicle body or mounting system or between the wheels, as well as vibrations caused by road conditions.
[0004] Vehicle disturbances are transmitted to the MDPS and act as a factor causing vibrations to be perceived by the driver. Disturbances whose frequency varies with vehicle speed are also transmitted to the MDPS and act as a factor interfering with the MDPS's control operation. Therefore, it is necessary to minimize the vibrations applied to the MDPS.
[0005] The related technology disclosed herein was published in Korean Patent Application Publication No. 10-2017-0067252 entitled “Electric Power Steering Apparatus”, published on June 16, 2017. Summary of the Invention
[0006] Various embodiments relate to a vibration damping device and method for an MDPS (motor-driven power steering) that can estimate disturbances applied to the MDPS and compensate for the disturbances in reverse, thereby reducing vibration.
[0007] In an embodiment, the vibration damping device of the MDPS may include: an adaptive control module configured to detect an error signal generated by interference from a torque signal of a torque sensor sensing the torque of the MDPS, and to generate a compensation signal for compensating the interference signal using the error signal; and an adaptive filtering module configured to generate a filtered signal using the vibration frequency of the interference of the MDPS, remove interference components from the current command output from the MDPS controller based on the filtered signal, and output a current command in which the interference is suppressed. The MDPS controller may generate a final current command based on the compensation signal and the current command in which the interference is suppressed, and control the motor of the MDPS according to the final current command.
[0008] The adaptive control module may include: an error signal detection unit configured to detect an error signal from a torque signal; and a compensation signal generation unit configured to generate a basic function by using the vibration frequency of the disturbance, generate a compensation signal by using the basic function, and then adjust the compensation signal according to the error signal to cancel the disturbance signal.
[0009] The error signal detection unit may include: a bandpass filter configured to output an error signal by filtering the torque signal; and a center frequency setting unit configured to set the center frequency of the bandpass filter according to the vibration frequency of the disturbance.
[0010] The compensation signal generation unit may include: a compensation signal detection unit configured to generate a rotation angle by integrating the vibration frequency of the disturbance, generate a basic function based on the rotation angle, and detect the compensation signal through the basic function; and a compensation signal adjustment unit configured to adjust parameters used to determine the amplitude and phase of the compensation signal, thereby reducing the amplitude of the error signal.
[0011] The adaptive filtering module may include: a filter signal detection unit configured to generate a rotation angle by integrating the vibration frequency of the disturbance, generate a basic function based on the rotation angle, and detect the filter signal using the basic function; and a filter signal adjustment unit configured to adjust parameters used to determine the amplitude and phase of the filter signal in order to reduce the error between the current command and the filter signal.
[0012] In an embodiment, the vibration reduction method of the MDPS may include: detecting an error signal generated by interference from a torque signal of a torque sensor that senses the torque of the MDPS via an adaptive control module, and generating a compensation signal for compensating the interference signal by using the error signal; generating a filter signal by using the vibration frequency of the interference of the MDPS via an adaptive filtering module, removing the interference component of the current command output from the MDPS controller based on the filter signal, and outputting a current command in which the interference is suppressed; and generating a final current command based on the compensation signal and the current command in which the interference is suppressed via the MDPS controller, and controlling the motor of the MDPS according to the final current command.
[0013] The generation of the compensation signal may include: detecting the error signal from the torque signal; generating a basic function by using the vibration frequency of the disturbance; generating a compensation signal by using the basic function; and then adjusting the compensation signal according to the error signal to cancel the disturbance signal.
[0014] The generation of the compensation signal may include: generating a rotation angle by integrating the vibration frequency of the disturbance, generating a basic function based on the rotation angle, and detecting the compensation signal using the basic function; and adjusting the parameters used to determine the amplitude and phase of the compensation signal so that the amplitude of the error signal is reduced.
[0015] The output of the current command may include: generating a rotation angle by integrating the vibration frequency of the disturbance, generating a basic function based on the rotation angle, and detecting a filtered signal using the basic function; and adjusting the parameters used to determine the amplitude and phase of the filtered signal in order to reduce the error between the current command and the filtered signal.
[0016] According to embodiments of this disclosure, the vibration reduction device and method for MDPS can estimate the frequency conversion interference applied to the MDPS and compensate for the interference in reverse, thereby reducing vibration.
[0017] Furthermore, MDPS's vibration damping devices and methods can reduce steering wheel vibration through simple numerical calculations without the need for existing dynamic modeling. Attached Figure Description
[0018] Figure 1 This is a block diagram illustrating the configuration of a vibration damping device for an MDPS according to an embodiment of the present disclosure.
[0019] Figure 2 It shows Figure 1 Configuration block diagram of the adaptive control module.
[0020] Figure 3 It shows Figure 1 The configuration block diagram of the adaptive filtering module.
[0021] Figure 4This is a diagram illustrating an example in which parameters according to an embodiment of the present disclosure converge based on simulation results.
[0022] Figure 5 This is a diagram showing the results (time data) of a compensation logic test using an actual vehicle according to an embodiment of the present disclosure.
[0023] Figure 6 This is a diagram showing the results of a compensation logic test (frequency analysis) using an actual vehicle according to an embodiment of the present disclosure.
[0024] Figure 7 This is a flowchart illustrating a vibration reduction method for MDPS according to an embodiment of the present disclosure. Detailed Implementation
[0025] In the following description, vibration damping devices and methods for MDPS (Motor Drive Power Steering) will be illustrated with reference to the accompanying drawings through various exemplary embodiments. It should be noted that the drawings are not to exact scale and the thickness of lines or the dimensions of components may be enlarged for ease of description and clarity. Furthermore, the terminology used herein is defined in consideration of the functionality of the invention and may be varied according to the user's or operator's habits or intentions. Therefore, the definitions of the terminology should be based on the overall disclosure set forth herein.
[0026] Figure 1 This is a block diagram illustrating the configuration of a vibration damping device for an MDPS according to an embodiment of the present disclosure. Figure 2 It shows Figure 1 Configuration block diagram of the adaptive control module. Figure 3 It shows Figure 1 The configuration block diagram of the adaptive filtering module. Figure 4 This is a diagram illustrating an example in which the parameters according to an embodiment of the present disclosure converge based on simulation results. Figure 5 This is a diagram illustrating the test results (time data) of compensation logic using an actual vehicle according to an embodiment of the present disclosure, and Figure 6 This is a diagram showing the results of a compensation logic test (frequency analysis) using an actual vehicle according to an embodiment of the present disclosure.
[0027] Reference Figures 1 to 3 The vibration damping device of MDPS according to the embodiments of the present disclosure includes an adaptive control module 100, an adaptive filtering module 200 and an MDPS controller 300.
[0028] The MDPS determines the vehicle's driving status using a torque sensor 20 for measuring the steering torque input to the steering wheel by the driver, a steering angle sensor (not shown) for measuring the steering angle or steering angular velocity of the steering wheel, and a vehicle speed sensor for measuring the vehicle speed. When the driver operates the steering wheel, the MDPS provides auxiliary torque via a motor based on the steering torque applied to the steering shaft.
[0029] During this process, the MDPS may be affected by vibrations caused by vehicle resonance, and the current command of the MDPS may also be affected by vibrations. That is, the current command for motor control of the MDPS provided from the MDPS controller 300 may also contain interference components.
[0030] The adaptive control module 100 detects an error signal generated by interference from the torque signal of the torque sensor 20 that senses the steering torque of the MDPS. The adaptive control module 100 generates a compensation signal to compensate for the interference signal by using the detected error signal.
[0031] The torque signal sensed by the torque sensor 20 may include drive torque, measurement noise, disturbance torque, and compensation torque. In particular, disturbance torque can be included in the torque signal through the vibration of the rack 10.
[0032] Reference Figure 2 The adaptive control module 100 includes an error signal detection unit 110 and a compensation signal generation unit 120.
[0033] The error signal detection unit 110 detects the error signal from the torque signal output by the torque sensor 20.
[0034] The error signal detection unit 110 includes a bandpass filter 112 and a center frequency setting unit 114.
[0035] The bandpass filter 112 outputs an error signal from the torque signal by filtering the torque signal sensed by the torque sensor 20. The torque signal sensed by the torque sensor 20 includes interference components.
[0036] The center frequency setting unit 114 detects the vibration frequency of the wheel caused by interference and sets the center frequency of the bandpass filter 112 to the vibration frequency of the wheel. The vibration frequency can be calculated based on the vehicle speed and the angular velocity of the motor 30.
[0037] In this case, based on the center frequency set by the center frequency setting unit 114, the bandpass filter 112 can filter the frequency of the corresponding frequency band, thereby detecting the error signal caused by interference components.
[0038] The compensation signal generation unit 120 generates a basic function of the compensation signal by using the vibration frequency of the interference, generates a compensation signal by using the generated basic function, and then adjusts the compensation signal according to the generated error signal to cancel the interference signal.
[0039] The compensation signal generation unit 120 includes a compensation signal detection unit 122 and a compensation signal adjustment unit 124.
[0040] The compensation signal detection unit 122 generates the rotation angle θ by integrating the vibration frequency of the interference.
[0041] The compensation signal detection unit 122 generates the basic function (sinθ, cosθ) of the compensation signal by using the generated rotation angle θ.
[0042] The compensation signal detection unit 122 detects the compensation signal (y = p1sinθ + p2cosθ) by using the generated basic function.
[0043] In the compensation signal, p1 and p2 represent the parameters used to determine the amplitude and phase of the compensation signal.
[0044] The compensation signal adjustment unit 124 adjusts the parameters used to determine the amplitude and phase of the compensation signal, thereby reducing the amplitude of the error signal.
[0045] That is, the compensation signal adjustment unit 124 controls the amplitude of the error signal to be reduced by adjusting the parameters of the compensation signal according to the error signal, thereby removing the interference signal (d = w1sinθ + w2cosθ).
[0046] The compensation signal adjusted by the compensation signal adjustment unit 124 is transmitted to the compensation signal transmission system and converted into torque of the MDPS system. The compensation signal transmission system may include all electronic and mechanical components, such as the MDPS controller 300, the motor 30, the motor controller, and gears, as long as these components are used to generate torque, and there are no specific limitations.
[0047] The steering torque generated by the compensation signal transmission system can be sensed by the torque sensor 20, and the torque signal sensed by the torque sensor 20 can be used to compensate for interference in the torque sensor 20.
[0048] The adaptive filtering module 200 generates a filtered signal by using the vibration frequency of the MDPS interference, removes the interference component of the current command output from the MDPS controller 300 based on the filtered signal, and outputs a current command in which the interference is suppressed.
[0049] Reference Figure 3 The adaptive filtering module 200 includes a filter signal detection unit 210 and a filter signal adjustment unit 220.
[0050] The filtered signal detection unit 210 generates a rotation angle θ by integrating the vibration frequency of the interference. The filtered signal detection unit 210 then uses the generated rotation angle θ to generate the basic function (sinθ, cosθ) of the filtered signal.
[0051] The filtered signal detection unit 210 detects the filtered signal (y) by using the generated basic function. model =p0+p1sinθ+p2cosθ).
[0052] In a filtered signal, p0, p1, and p2 represent parameters used to determine the amplitude and phase of the filtered signal.
[0053] The filter signal adjustment unit 220 adjusts the parameters used to determine the amplitude and phase of the filter signal, thereby reducing the error between the filter signal and the current command of the MDPS controller 300.
[0054] That is, the filter signal adjustment unit 220 receives a current command from the MDPS controller 300. The filter signal adjustment unit 220 detects errors by comparing the current command received from the MDPS controller 300 with the filter signal detected by the filter signal detection unit 210.
[0055] The error corresponds to the value obtained by subtracting the filtered signal detected by the filtered signal detection unit 210 from the current command received from the MDPS controller 300.
[0056] When an error is detected, the filter signal adjustment unit 220 adjusts parameters p0, p1 and p2 to reduce the magnitude of the error.
[0057] The filter signal adjustment unit 220 adjusts parameters p0, p1, and p2 to remove interference signals (p1sinθ + p2cosθ) from the filtered signal. When only parameter p0 is corrected, it is difficult to distinguish the interference signal from other signals that are not interference signals, making it difficult to remove only the interference signal. Therefore, the filter signal adjustment unit 220 removes interference signals by adjusting parameters p0, p1, and p2.
[0058] Since the interference signal (p1sinθ+p2cosθ) is removed by the filter signal adjustment unit 220, the current command output by the filter signal adjustment unit 220 is p0. At this time, p0 is a low-frequency smoothed signal.
[0059] That is, the filter signal adjustment unit 220 generates a filtered signal from which the interference signal has been removed, i.e., a current command in which the interference is suppressed, and inputs the generated current command to the MDPS controller 300.
[0060] The MDPS controller 300 receives a compensation signal from the adaptive control module 100, receives a current command from the adaptive filtering module 200 in which interference is suppressed, and generates a final current command based on the compensation signal and the current command in which interference is suppressed. The MDPS controller 300 controls the MDPS motor 30 according to the generated final current command.
[0061] Reference Figure 4 Simulation results of a vibration damping device for an MDPS according to an embodiment of the present disclosure are shown, where parameters p0, p1, and p2 converge to target parameters 0.1, 1.0, and 1.0, respectively. At this point, the convergence time can be changed based on the magnitude of the updated gain.
[0062] Figure 5 The test results using actual vehicles are shown. The test conditions were a vehicle speed of 150 km / h and a vibration frequency range of 30 Hz to 10 Hz.
[0063] Figure 5 The diagrams comparatively illustrate the states where the compensation logic of the MDPS vibration damping device is off and on. (Refer to...) Figure 5 The MDPS torque is greater when the compensation logic is turned on than when the compensation logic is turned off.
[0064] That is, when the compensation logic is enabled, a compensation signal is added to suppress interference signals contained in the steering torque of the MDPS. As a result, the MDPS torque in the state where the compensation logic is enabled becomes greater than the MDPS torque in the state where the compensation logic is disabled.
[0065] Figure 6 The test results using actual vehicles are shown. The test conditions were a vehicle speed of 150 km / h and a vibration frequency range of 30 Hz to 10 Hz.
[0066] Figure 6 The amplitude of the vibration is shown to be reduced by up to 60% when the compensation logic is on, compared to the amplitude of the vibration when the compensation logic is off.
[0067] Accordingly, the vibration damping device of the MDPS according to the embodiments of the present disclosure can define an error signal even without dynamic modeling, and reduce steering wheel vibration simply by measurement.
[0068] In the following text, reference will be made to Figure 7 A vibration reduction method for MDPS according to embodiments of the present disclosure is described in detail.
[0069] Figure 7This is a flowchart illustrating a vibration reduction method for MDPS according to an embodiment of the present disclosure.
[0070] Reference Figure 7 In step S110, torque sensor 20 senses the MDPS torque signal.
[0071] In step S120, the error signal detection unit 110 detects an error signal from the torque signal output by the torque sensor 20. In this case, the center frequency setting unit 114 detects the vibration frequency of the wheel caused by the interference and sets the center frequency of the bandpass filter 112 to the vibration frequency of the wheel. The bandpass filter 112 outputs an error signal from the torque signal by filtering the torque signal sensed by the torque sensor 20.
[0072] In step S130, the compensation signal detection unit 122 generates a rotation angle θ by integrating the vibration frequency of the disturbance, and generates the basic function (sinθ,cosθ) of the compensation signal by using the generated rotation angle θ.
[0073] Furthermore, in step S140, the compensation signal detection unit 122 detects the compensation signal (y = p1sinθ + p2cosθ) by using the generated basic function.
[0074] In this case, in step S150, the compensation signal adjustment unit 124 adjusts the parameters p1 and p2 used to determine the amplitude and phase of the compensation signal, so that the amplitude of the error signal is reduced.
[0075] In step S210, the filter signal detection unit 210 generates a rotation angle θ by integrating the vibration frequency of the interference, and generates the basic function (sinθ,cosθ) of the filter signal by using the generated rotation angle θ.
[0076] In step S220, the filtered signal detection unit 210 detects the filtered signal (y) by using the generated basic function. model =p0+p1sinθ+p2cosθ).
[0077] Then, in step S230, the filter signal adjustment unit 220 adjusts the parameters used to determine the amplitude and phase of the filter signal, thereby reducing the error between the filter signal and the current command of the MDPS controller 300.
[0078] That is, the filter signal adjustment unit 220 detects the error by comparing the current command received from the MDPS controller 300 with the filter signal detected by the filter signal detection unit 210, and adjusts the parameters p0, p1 and p2 to reduce the magnitude of the detected error.
[0079] Then, in step S300, the MDPS controller 300 receives a compensation signal input from the adaptive control module 100, receives a current command from the adaptive filtering module 200 in which interference is suppressed, and generates a final current command based on the compensation signal and the current command in which interference is suppressed.
[0080] In step S310, the MDPS controller 300 generates torque by controlling the MDPS motor 30 according to the generated final current command.
[0081] Accordingly, the vibration reduction device and method for MDPS according to the embodiments of the present disclosure can estimate the frequency conversion interference applied to the MDPS and compensate for the interference in reverse, thereby reducing vibration.
[0082] Furthermore, the vibration reduction device and method of MDPS according to the embodiments of this disclosure can reduce steering wheel vibration through simple numerical calculations without the need for existing dynamic modeling.
[0083] The embodiments described in this specification can be implemented, for example, as methods or processes, devices, software programs, data streams, or signals. Although features are discussed only in a single context (e.g., only in methods), the discussed features can be implemented in another type (e.g., apparatus or program). An apparatus can be implemented in suitable hardware, software, or firmware. The method can be implemented in a device such as a processor, which generally refers to a processing device including, for example, a computer, microprocessor, integrated circuit, or programmable logic device. The processor also includes communication devices such as computers, cellular phones, PDAs (personal digital assistants), and other devices that facilitate information communication between end users.
[0084] While exemplary embodiments of this disclosure have been disclosed for illustrative purposes, those skilled in the art will understand that various modifications, additions, and substitutions are possible without departing from the scope and spirit of this disclosure as defined in the appended claims. Therefore, the true technical scope of this disclosure should be defined by the appended claims.
Claims
1. A vibration damping device for motor-driven power steering, comprising: An adaptive control module is configured to detect an error signal generated by interference from a torque signal of a torque sensor that senses the torque of the motor-driven power steering, and to generate a compensation signal for compensating the interference signal by using the error signal. as well as An adaptive filtering module is configured to generate a filtered signal using the vibration frequency of the disturbance caused by the motor-driven power steering, remove the interference component from the current command output from the motor-driven power steering controller based on the filtered signal, and output a current command with the interference suppressed. The motor-driven power steering controller generates a final current command based on the compensation signal and the current command with suppressed interference, and controls the motor driving the power steering according to the final current command. The adaptive filtering module includes: A filtered signal detection unit is configured to generate a rotation angle by integrating the vibration frequency of the disturbance, generate a basic function based on the rotation angle, and detect the filtered signal using the basic function; and The filter signal adjustment unit is configured to adjust parameters used to determine the amplitude and phase of the filter signal in order to reduce the error between the current command and the filter signal.
2. The vibration damping device according to claim 1, wherein The adaptive control module includes: An error signal detection unit is configured to detect the error signal from the torque signal; and The compensation signal generation unit is configured to generate a basic function by using the vibration frequency of the interference, generate the compensation signal by using the basic function, and then adjust the compensation signal according to the error signal to cancel the interference signal.
3. The vibration damping device according to claim 2, wherein The error signal detection unit includes: A bandpass filter is configured to output the error signal by filtering the torque signal; and The center frequency setting unit is configured to set the center frequency of the bandpass filter according to the vibration frequency of the interference.
4. The vibration damping device according to claim 2, wherein The compensation signal generation unit includes: A compensation signal detection unit is configured to generate a rotation angle by integrating the vibration frequency of the disturbance, generate a basic function based on the rotation angle, and detect the compensation signal using the basic function; and The compensation signal adjustment unit is configured to adjust parameters used to determine the amplitude and phase of the compensation signal, thereby reducing the amplitude of the error signal.
5. A vibration reduction method for motor-driven power steering, comprising: The adaptive control module detects the error signal generated by the interference from the torque signal of the torque sensor that senses the torque of the motor drive power steering, and generates a compensation signal to compensate for the interference signal by using the error signal. The adaptive filtering module generates a filtered signal by using the vibration frequency of the interference from the motor-driven power steering. Based on the filtered signal, the interference component of the current command output from the motor-driven power steering controller is removed, and the current command with the interference suppressed is output. as well as The motor-driven power steering controller generates a final current command based on the compensation signal and the current command with suppressed interference, and controls the motor driving the power steering motor according to the final current command. The output of the current command includes: A rotation angle is generated by integrating the vibration frequency of the disturbance; a basic function is generated based on the rotation angle; and a filtered signal is detected using the basic function. The parameters used to determine the amplitude and phase of the filtered signal are adjusted to reduce the error between the current command and the filtered signal.
6. The vibration reduction method according to claim 5, wherein, The generation of the compensation signal includes: Detect the error signal from the torque signal; and A basic function is generated by using the vibration frequency of the interference, and a compensation signal is generated by using the basic function. The compensation signal is then adjusted according to the error signal to cancel the interference signal.
7. The vibration reduction method according to claim 6, wherein, The generation of the compensation signal includes: A rotation angle is generated by integrating the vibration frequency of the disturbance; a basic function is generated based on the rotation angle; and the compensation signal is detected using the basic function. The parameters used to determine the amplitude and phase of the compensation signal are adjusted so that the amplitude of the error signal is reduced.